Rotary electric switch rotor construction



Sept. 16, 1 969 K. c. ALLISON ROTARY ELECTRIC SWITCH ROTOR CONSTRUCTION Filed March 8. 1968 w m a 5 Q, w M102, m M 115 2 2J2 Tm 4 1 3 "a I |||i1l| a; M Z W q I M mfi 1% w WW 4.? A %1 k! 4% m V W 9 f 1 Z W 4 7M 5 9 3 Z 5. a 5 ,4.

United States Patent 3,467,792 ROTARY ELECTRIC SWITCH ROTOR CONSTRUCTION Kenneth C. Allison, 1546 8. Shore Drive, Crystal Lake, Ill. 60014 Filed Mar. 8, 1968, Ser. No. 711,706 Int. Cl. H01h 19/54, 21/76 US. Cl. 200-11 6 Claims ABSTRACT OF THE DISCLOSURE An improved rotor construction for a multi-contact rotary switch as disclosed herein includes a molded rotor body having a rotor contact blade supporting portion in which the shank portion of each rotor contact blade is embedded and the area between the opening in the rotor for occupancy by the rotor operating shaft and the area containing said shank portions of the contact blades is provided with an axially extending recess in which radially extending inner ends or terminals of said rotor contact blades are available for welded or soldered connection with a bridge member in said recess when said terminals are upended into axially extending position. Each terminal is offset from the shank portion of the contact blade associated therewith in a direction away from the terminal in axially paired relation thereto so as to bring said terminal, when upended, closer to the surface of the rotor and accordingly more accessible for the production of a soldered or welded connection with the surface of a bridge member facing said terminals.

This invention relates to improvements in the design and construction of multiple contact rotary switch units.

More particularly it is concerned with rotary switch units of the type wherein contact fingers having portions embedded in a molded rotor body and which occupy aligned positions in separate planes spaced apart axially of the rotor body are provided with inner terminal portions or lugs which are joined by a soldered or welded connection to a conductive bridge member which occupies an open clearway coextensive with the axial dimension of the rotor to establish an electrical link between contact members secured to axially opposed sides of a stator via said bridge member and the terminals or lugs of the axially aligned rotor contact fingers to which the bridge member is joined. In switch units of this type the rotor body is initially formed with a cavity or recess which defines an open clearway intersecting both faces of the rotor except for radially extending terminals or lugs of the axially aligned rotor contact fingers and a break away or rupturable section of the opposite face portions of the rotor body in which said radially extending terminals or lugs are contained pending upending of the terminals in the direction of the face of the rotor body nearest said terminal and rupture of the breakaway section incident to such upending action. Such disposition of the terminals in axially extending relation is required to afford access to the terminal in the production of a soldered or welded connection with the surface of the bridge member facing said terminal. Since the region occupied by the bridge member is necessarily confined to the area of the rotor surrounding the opening in the rotor which receives the rotor operating shaft, the use of such bridge members in miniaturized rotary switch units consequently restricts the radial dimension of the area available for occupancy by the rotor contact terminals while in radially extending position with the result that the terminal when upended does not provide exposure of the terminal as needed to 3,467,792 Patented Sept. 16, 1969 "ice obtain a reliable soldered or welded connection between the terminal and the bridge member associated therewith.

In a rotor construction embodying the features of this invention, it is an object to provide rotor contact fingers having portions embedded in a molded rotor body and terminals forming inner extensions of said fingers which are extendable axially of the rotor a distance greater than the radial dimension of the area occupied by said terminals While in radially extending position so as to assure ample access to the terminals as needed for the production of a soldered or welded connection between a bridge member and the surface of the upended terminals of the rotor contact fingers facing said bridge member.

Other and further objects, features and advantages of the present invention will be apparent to one skilled in the art from the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a fragmentary plan view of a rotary switch unit embodying the features of this invention.

.FIG. 2 is an axial section taken along line 22 of FIG. 1.

FIG. 3 is an enlarged fragmentary section taken along line 3-3 of FIG. 1.

FIG. 4 is a fragmentary plan view of a portion of the rotor containing the contact terminal as it appears in the break away section of the rotor face preparatory to rupture of said section and the step of upending the contact terminal into an axially extending position as shown in FIGS. 2 and 3.

As shown in the drawings, the stator of a rotary switch unit exemplifying this invention is in the form of an annular wafer 10 of suitable insulating material. Stator contact members 11, 12 and 13, each consist of a metal strip arranged radially of the central opening 14 of the stator and is formed with a spoon-shaped inner end 15 to engage with corresponding contacts carried by a rotor. Each of the stator contact members is fixed to the stator by. means of a rivet 16 which fits a rectangular shaped opening in the stator contact as well as a selected rivet accepting opening 17 in the stator in registry therewith. An illustrated in FIG. 1, the stator contact members 11 and 12 are thus secured to the front or exposed face of the stator while the stator contact member 13 is secured to the rear or opposite face of the stator. Each of the stator contact members is also provided with an outer soldering terminal lug 18.

The rotor, which is bent shown in FIGS. 2 and 3, includes a hub member 19 of molded insulating material such as nylon, Delrin or other relatively friction free material. The hub member 19 is provided with a rotor operating shaft opening 20 which when brought into coincidence provides a passage in which the flattened sides of a rotor operating shaft 21 has engagement to cause the hub member to be driven or rotated in response to rotation of the shaft 21 about its longitudinal axis. The hub member 19 is of such siZe as to be accommodated within the confines of the opening 14 in the stator. The edges of the opening 14 furnish a bearing surface against which the hub member rides when the shaft 21 is operated to rotate the hub member while the hub member occupies an operative position within the stator opening and the surfaces of the rotor hub facing in opposite directions axially of the shaft 21 are within the confines of planes containing opposite face portions of the stator bordering said stator opening.

A pair of disks 22 and 23, each provided with a rotor operating shaft opening 24 to form a passage i which the flattened sides of the shaft 21 has non-rotative engagement accordingly have driven connection with the shaft in unison with rotation of the rotor hub member 19. These disks 22 and 23, as shown in the drawings, occupy positions in flanking relation to the rotor hub member 19 and said disks are of such radial dimension as to provide border portions which overlap opposite face portions of the stator surrounding the stator opening occupied by the hub member 19. Means for securing the disks and the rotor hub member in rigidly joined relation and thereby operative to retain the rotor hub Il'lGIIlbGfi'WllhlIl the confines of the stator opening 14 include coupling fingers 25 which are defined by axial extensions of the rotor hub member along opposite edge portions of the shaft receiving opening 20 in said hub member. 'lhe coupling fingers which extend in one axial direction from the hub member have entry to pockets 26 formed in oppos te edge portions of the shaft receiving opening in the disk 22 'While the coupling fingers extending in the direction of disk 23 have entry to corresponding pockets formed n opposite edge portions of the shaft receiving opening in the disk 23. It will be noted that the coupling fingers provide a surface with which the shaft 21 has close engagement to restrain withdrawal of the fingers from the pocket associated therein in directions inwardly of the area containing the shaft while tab portions 27 at the axially outermost ends of the fingers 25 have overlapping engagement with surfaces of the disks associated therewith along areas bordering said pockets containing the fingers which are thereby effective to lock the disks against separation from the rotor hub member Without the use of additional fastening means.

The disks 22 and 23 are preferably formed of molding material having superior dielectric characteristics such as glass alkyd or diallyl phthalate or compositions of substantially equal insulating quality so as to provide a molded insulating support for the shank portions 28 of rotor contact fingers which have blade sections extending radially beyond the edges of the disks for selective engagement with the stator contact members. The area of each of the rotor disks 22 and 23 between the shaft opening 24 of the disks and the shank portions 28 of the rotor contact fingers embedded in said disks is provided with an axially extending recess 29 which in conjunction with a corresponding opening 30 provided in the hub member 19 in axial alignment with each recess 29 in the disks defines a clearway coextensive with the axial dimension of the rotor assembly except for an inner terminal 31 defined by an extension of the shank of each rotor contact finger secured to rotor disk 22 which terminal 31 is attached to or embedded within the confines of an end wall 22 defined by an integral breakaway section of the outermost face of rotor disk 22 and an inner terminal 32 defined by an extension of the shank of each rotor contact finger secured in rotor disk 23 which terminal 32 is attached to or embedded within the confines of an end wall 23 defined by a integral breakaway section of the outermost face of rotor disk 23. Thus each inner terminal 31 of the contact fingers secured to disk 22 is in axial alignment with a corresponding terminal 32 of the contact fingers in disk 23 as well as the recess 29 in each disk 22 and 23 and the opening 30 in hub member 19 axially aligned with said recess 29. As shown in FIGS. 2 and 3, the inner terminal 31 of the contact fingers in disk 22 While embedded in the break-away section of disk 22 occupies a radially extending position in offset relation to the shank portion of its associated contact fingers in a direction away from the inner terminal 32 of the contact finger in disk 23 axially aligned therewith. Each terminal 31 is thus annexed to its associated contact finger by means of a relatively short junction 33 extending axially of the rotor body. Likewise the inner terminal 32 of the contact fingers in disk 23 while embedded in the break-away section of disk 23 is annexed to its associated contact fingers by means of a similar short junction 34 extending axially of the rotor body whereby the terminal 32 of each finger in disk 23 is offset axially of its shank portion in a direction away 4. from the inner terminal 31 of the contact finger in disk 22 axially aligned therewith.

The junctions thus provided between the terminals 31 and 32 respectively and the shank portions of the contact fingers associated therewith provide an axial extension of the terminals 31 and 32 when said terminals are up ended for the purpose of establishing an electrical connection with a selected set of axially paired terminals 31 and 32 by means of a conductive bridging member 35 as shown in FIG. 2 and in FIG. 3, upon rupture of the break-away sections containing or attached to said terminals so as to provide the clearway for the reception of said bridge member 35. Due to the projection of the terminals 31 and 32 outside the confines of the clearway thus formed to accommodate the bridge member, there is ample exposure of the terminals for producing a soldered orwelded connection between the opposite ends of the bridge member 35 and the surfaces of the terminals 31 and 32 facing said bridge member.

As shown in FIG. 2, the bridge member 35 and the terminals 31 and 32 conductively joined to said bridge member 35 in conjunction with the rotor contact fingers with which said terminals are associated provide an electrical connection between the stator contact member 12 on one side of the stator and the stator contact member 13 on the opposite side of the stator.

It is important to observe that a rotor assembly embodying the feature of this invention as illustrated in FIG. 1 eliminates the use of fastening means requiring areas of the rotor which coincide with a continuous circular band containing the embedded portions of the rotor contact fingers and the inner terminals thereof. Accordingly, no switching position is lost to accommodate such fastening means.

What is claimed is:

l. A rotary switch including a stator, a rotor of molded insulating material having opposed first and second faces and a non-circular opening connecting said faces for engagement with an operating shaft, a central opening in said stator ocuppied by said rotor, first and second rotor contact blades, each having a shank portion, said rotor having contact blade supporting portions between said faces in which the shank portion of said contact blades are embedded in radially extending aligned spaced apart relation axially of said rotor and each of said blades having an exposed end portion extending radially beyond the edge of said rotor, an axially extending recess provided in said rotor within an area radially inwardly of the area occupied by said shank portions of said contact blades, said recess defining a clearway between said first and second faces of the rotor except for a radially projecting extension of the shank of said first rotor contact blade defining an inner terminal of said first rotor contact blade, and except for a similar radially projecting extension of the shank of said second rotor contact blade defining an inner terminal of said second rotor contact blade, each of said terminals occupying a position in offset relation to the shank portion of the rotor contact blade associated therewith in an axial direction away from the terminal of the rotor contact blade axially paired therewith pending upending of said terminals into a position extending axially of said clearway in a direction away from the terminal in axially paired relation thereto, each of said terminals being dimensioned to project outside the confines of said clearway when in such axially extended position whereby a conductive bridge member extending axially of said clearway and conductively joined to said terminals at said projecting ends cooperate to establish an electrical connection with a stator contact blade engaging the first rotor contact blade and a stator contact blade engaging the second rotor contact blade.

2. A rotary switch according to claim 1 wherein the rotor contact blade supporting portion containing said first rotor contact blade is defined by a first rotor disk, and the rotor contact blade supporting portion containing said second rotor contact blade is defined by a second rotor disk, and said disks are joined in rigid assembly by a separate hub member sandwiched between said first and second rotor disks.

3. A rotary switch according to claim 2 wherein said first and second rotor disks and said hub member are joined by fastening means remote from an area coincident with a continuous circular band containing the embedded portions of the rotor contact blades.

4. A rotary switch according to claim 2 wherein said first and second rotor disks and said hub member are joined by fingers formed integrally with said hub member and confined to areas of the disks and the hub member adjoining the operating shaft opening in said rotor.

5. A rotary switch according to claim 1 wherein the terminal of said first rotor contact blade is embedded an integral breakaway section of the first face of said rotor when the terminal of said first rotor contact blade is in radially extending positio and wherein the terminal of said second rotor contact blade is embedded in an integral breakaway section of the second face of said rotor when the terminal of said first rotor contact blade is is in radially extending position.

6. A rotary switch according to claim 1 wherein the terminal of said first rotor contact blade is attached to an integral breakaway section of the first face of said rotor when the terminal of said first rotor contact blade is in radially extending position and wherein the terminal of said second rotor contact blade is attached to an integral breakaway section of the second face of said rotor when the terminal of said second rotor contact blade is in radially extending position.

References Cited UNITED STATES PATENTS 3,213,211 10/1965 Allison. 3,308,248 3/1967 Stephan et al.

ROBERT K. SCHAEFER, Primary Examiner J. R. SCO'IT, Assistant Examiner US. a. X.R. 

